Operating Conditions Assessment For A Grid-Connected Wind Turbine Generator System

Nowadays the installed capacity of wind power increase rapidly in China and megawatts wind turbine generator system (WTGS) and 100 megawatts wind farms are also developing quickly. The large-scale wind farms are also developing from onshore to offshore, even to abyssal regions, so that the accurate monitoring and condition assessment for WTGS have become important attentions and focuses to avoid the fault and cascading failure due to more severe offshore environments and higher maintenance cost compared with the onshore wind power. It is meaningful to optimize the maintenance strategy of wind farms and assure efficient grid-connected for a WTGS. Based on the mastery of working principle and control principle of WTGS, the following research work was to be carried:â‘ The operation characteristics of control system and monitoring quantities are mastered based on in-depth understanding of the operating principle and basic structure of a grid-connected WTGS. In addition,the common failure modes, fault mechanism, stop loss and fault statistics data are also analyzed.â‘¡Because the fuzzy comprehensive evaluation does not need to rely on the much more test data, the method may be a suitable method to assess the operating condition of WTGS by Only use of on-line monitoring information. Firstly, an operational conditions evaluation indices system of WTGS is proposed, and a degree of inferiority indicator is adapted to quantize the evaluation indices by limiting values defined. Secondly, in order to allocate reasonably the weight of evaluation indices, by analytic hierarchy process (AHP). The constant weights are set .In addition, the variable weight was obtained based on the constant weight by the traditional variable weights method. Thirdly, by using the fuzzy comprehensive evaluation method, the model of operating condition assessment for the WTGS is proposed. Finally, the model is tested by using the actual monitoring data.â‘¢Considering the variable speed constant frequency operation characteristic of the WTGS, evaluation indices is quantized. The fitting functions and dynamic limiting values for some of evaluation indices are obtained by the Bin method. Then, an improved variable weights method was proposed. In addition, the extended relation functions are adapted in the matter-element analysis theory, and the matter-element model of operating conditions assessment for the WTGS were proposed and compared. â‘£By using the two assessment methods proposed, an operating condition assessment software of the WTGS is invented based on the LabVIEW platform, and its validity is proved by some actual data through the simulation.The research results may be applied to control system of a WTGS and the SCADA system of wind farms, so that higher reliability and higher availability of a grid-connected WTGS is obtained and operation maintenance cost is reduced. It has important practical value for realizing condition maintenance of the grid-connected WTGS.